Search Publications
On the driver of relativistic effect strength in Seyfert galaxies
Bianchi, S.; Guainazzi, M.; Longinotti, A. L. +2 more
Context. Spectroscopy of X-ray emission lines emitted from accretion discs around supermassive black holes is one of the most powerful probes of the accretion flow physics and geometry, while also providing in principle observational constraints on the black hole spin. Previous studies have suggested that relativistically broadened line profiles a…
An X-ray underluminous cluster of galaxies in the 4Ms CDFS observations
Fiore, F.; Castellano, M.; Pentericci, L. +8 more
Aims: We investigate the properties of cluster ClG 0332-2747 at z = 0.734 in the GOODS-South field, which was undetected in the Chandra 2Ms observations. We explore possible scenarios to explain the discrepancy between its low X-ray emission and that expected from the M - LX relation.
Methods: We use the large public spectrosc…
HD 144432: A young triple system
Carmona, A.; Henning, Th.; van Boekel, R. +3 more
We present new imaging and spectroscopic data of the young Herbig star HD 144432 A, which is a well-known binary star with a separation of 1.47″. High-resolution NIR imaging data obtained with NACO at the VLT reveal that HD 144432 B itself is a close binary pair with a separation of 0.1″. High-resolution optical spectra, acquired with FEROS at the…
XMM-Newton observations of the pre-polar HS0922+1333
Schwope, A. D.; Schwarz, R.; Vogel, J.
We report on XMM-Newton and accompanying phase-resolved optical observations of HS0922+1333, one out of nine pre-polars. It shows X-ray and UV variability correlated with the visibility of the main accretion spot. The spectral X-ray properties reveal a low temperature thermal plasma of ~1 keV with FX more than one order of magnitude bel…
A close look at the Centaurus A group of galaxies. III. Recent star formation histories of late-type dwarfs around M 83
Crnojević, D.; Grebel, E. K.; Cole, A. A.
Aims: We study the resolved stellar populations of dwarf galaxies in the nearby Centaurus A/M 83 group of galaxies. Our goal is to characterize their evolutionary history and to investigate eventual similarities or differences with the dwarf population in other group environments.
Methods: This work presents the analysis of five late-typ…
Dipping in CygnusX-2 in a multi-wavelength campaign due to absorption of extended ADC emission
Wilms, J.; Spencer, R. E.; Hanke, M. +5 more
We report results of one-day simultaneous multiwavelength observations of CygnusX-2 using XMM, Chandra, the European VLBI Network and the XMM Optical Monitor. During the observations, the source did not exhibit Z-track movement, but remained in the vicinity of the soft apex. It was in a radio quiescent/quiet state of <150 µJy. Strong dip …
A molecular cloud within the light echo of V838 Monocerotis
Deguchi, S.; Tylenda, R.; Kamiński, T.
Context. V838 Mon is an eruptive variable, which exploded in 2002. It displayed the most spectacular light echo ever observed. However, neither the origin of the reflecting matter nor the nature of the 2002 outburst have been firmly constrained.
Aims: We investigate the nature of the CO radio emission detected in the field of the light echo. …
X-ray spectroscopy of the Compton-thick Seyfert 2 ESO 138 - G1
Fiore, F.; Bianchi, S.; Vignali, C. +2 more
We report on our analysis of XMM-Newton observations of the Seyfert 2 galaxy ESO 138-G1(z = 0.0091). These data reveal a complex spectrum in both its soft and hard portions. The 0.5-2 keV band is characterized by a strong "soft-excess" component with several emission lines, as commonly observed in other narrow-line AGN. Above 3 keV, a power-law fi…
The high resolution X-ray spectrum of SNR 0506-68 using XMM-Newton
Vink, J.; Broersen, S.; Raymond, J. +1 more
Aims: We study the supernova remnant 0506-68 in order to obtain detailed information about, among other things, the ionisation state and age of the ionised plasma.
Methods: Using the Reflection Grating Spectrometer (RGS) onboard the XMM-Newton satellite we are able to take detailed spectra of the remnant. In addition, we use the MOS data…
XMM-Newton observation of the enigmatic object WR 46
Gosset, E.; Nazé, Y.; Rauw, G. +5 more
Aims: To further investigate the nature of the enigmatic object WR 46 and better understand the X-ray emission in massive stars and in their evolved descendants, we observed this variable object for more than two of its supposed cycles. The X-ray emission characteristics are appropriate indicators of the difference between a genuine Wolf-Raye…